Or are they?

You know the ones I mean.  Those little throw-away details which don’t actually contribute to the plot.  Like this one, from the article I was talking about yesterday:

The experts assembled by the Hansard Society, in a windowless conference room in an obscure corner of the Parliamentary estate, were divided on this one.

Does it matter that the conference room had no windows?  I can’t think of any reason for it to affect anything that follows.  Likewise it doesn’t really matter that the conference room was in an obscure corner.  What matters is that experts were assembled to discuss the issue, and that they were divided.

Except that the little details contribute to the overall feel of the piece.  We know, from those few words, that the meeting was not the most important that went on that day.  It has the feel of being slightly hidden, slightly shunned by most normal folk.  The idea they were discussing is not taken seriously by parliamentarians.

What little details have you included in your work lately, to build atmosphere, or give background information to your readers?